From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH] cgroup: fix the retry path of cgroup_mount()
Date: Thu, 17 Apr 2014 11:20:48 -0400
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To: Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
Cc: LKML <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Cgroups <cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>

On Thu, Apr 17, 2014 at 01:53:08PM +0800, Li Zefan wrote:
> If we hit the retry path, we'll call parse_cgroupfs_options() again,
> but the string we pass to it has been modified by the previous call
> to this function.
> 
> This bug can be observed by:
> 
>   # mount -t cgroup -o name=foo,cpuset xxx /mnt && umount /mnt && \
>     mount -t cgroup -o name=foo,cpuset xxx /mnt
>   mount: wrong fs type, bad option, bad superblock on xxx,
>          missing codepage or helper program, or other error
>   ...
> 
> The second mount passed "name=foo,cpuset" to the parser, and then it
> hit the retry path and call the parser again, but this time the string
> passed to the parser is "name=foo".
> 
> To fix this, we avoid calling parse_cgroupfs_options() again in this
> case.
> 
> Signed-off-by: Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>

Applied to cgroup/for-3.15-fixes.

Thanks.

-- 
tejun